Radio Society tries to beat back powerline networks The Radio Society of Great Britain has set up a Spectrum Defence Fund to challenge Ofcom's view of powerline networking. The RSGB reckons it's going to cost £75,000 to fund a Judicial Review, which is what's needed to kick Ofcom into reconsidering powerline devices. Donations are invited though the RSGB site, with any excess …
And that when I'm not a radio amateur. These people are pretty rare indeed, for they usually know what they're doing, not to mention that they tend to be nice enough to lend a hand in case of emergencies and disasters. If they say shoddy shielding in powerline networking kit is a problem, I tend to believe them.
Besides, the 2.4GHz band is crowded enough already and the 5GHz band is shared with high-power users like traffic radar resulting in noticeable interference. If powerline network transmissions aren't properly shielded they aren't likely to be properly confined in their various bands and are therefore likely to be a hard-to-detect-for-the-layman nuisance if not worse.
So yes, I do laud and support this initiative.
wheres the one that supports offcom and beats the radio hamms over the head for allowing the unrestricted abuse of 2.4 ghz by wifi junkies.
them pesky hamms have done more damage by not standing up to offcom and allowing them to piss away the spectrum on cancer causing toys for the city yobs.
Click,,,,hmmmmm....helo is this on.ok......KEEP HOMEPLUG, ITS SAFER THAN WIFIWALLIES!!!
Its not just the "household wiring" that radiates the signal, but the distribution power lines as well. Any marginal connection has diode properties, the result is that 2 or more frequencies combine into the sums and the differences of the input frequencies, and radiation on these unintended frequencies.
Shortwave radio depends on low noise on the frequency band so that distant receivers can hear the signal. Even the slightest imperfection implementing broadband power line (BPL) raises the noise floor rendering shortwave and weak-signal radio useless.
DSL can produce similar problems but is run on twisted pair cabling which contains the signal much much better than an unshielded power cable.
The whole point of BPL is to save the effort of running new wires. Someone should tell the unions that BPL will cost jobs.
Environmentalists should also oppose BPL as it pollutes the electromagnetic spectrum.
You're better using 802.11 wireless than trying to send data over the mains wiring in a home. If it's being used for power distribution, it will never work well for high speed data. Here in the US we have tried it and found the companies pushing it are not able to compete with fiber and cable systems. The Broadband over Power Line companies remain in business only due to the Bush FCC's backing of their business interests to the detriment of other users of the airwaves.
That's an oxymoron!
In my area there are so many wireless networks (about 20 or so) that I can pick up, I'm surprised I even pick up my own network sometimes. Not to mention I'm lucky if I get more than 10 meg.
If you ask me, if you want fast networking, CAT5 or CAT6 cabling round the house is a better solution (I only tend to use wireless on the Wii and laptop when I'm doing basic browsing, anything quicker and it's CAT5 for me (I do have a pair of these offending adaptors but found I didn't need them, not to mention they suck a whole lot of power).
By the way, I welcome the radio ham overlords.
Rob
It's not just Radio Amateurs and Short Wave listeners that are affected, the Electromagnetic Conformance industry are also deeply concerned with PLT. The EMC Journal has been running articles written by some of the leading figures in the field who cannot understand why Ofcom are allowing PLT to market.
Ofcom seem willing to allow PLT products onto the market that exceed agreed acceptable emissions levels by a factor of about 1000 . These have been demonstrated to cause harmful interference, so are paving the way for other manufacturers to disregard the law by cutting their production costs by not fitting costly suppression components. This is the big problem. Opening Pandoras box to disregard EMC law has consequences for everyone. At the moment its HF spectrum; next it may be your baby monitors and then FM.
The whole idea of EMC law was to ensure that electronic products don't interfere with each other. It has worked very well up until now.....
See http://f1.grp.yahoofs.com/v1/gGwiS3NRF--OpTi9ZaDo4HZiCzDlYYfgFr2zbmtk_lQnKcYjr8g0hsxtIOHFzUaV-ZJ4mEO4JDpEesd5Xy6OGA/EMC%20Journal%20%2383.pdf
This problem is much more significant than your article suggests.
The total number of complaints for this technology is already the fourth highest and this is compared to massive volumes of products sold for decades for example lighting products. The rate of complaints per units sold is far higher than for any other type of device. There is already ample evidence that this is a problem and the regulator should be doing it's job and regulating to prevent a problem becoming widespread.
The biggest problem is of setting a precedent. My company designs products all the time for lots of different customers all of these products need to meet EMC standards and it costs us time and effort to ensure that they do comply. If a precedent is set that products do not need to meet the standards then there will be massive pressure to allow all products to ignore EMC standards. If this happens there will be a lot of problems.
Since complaints to Ofcom and the No.10 petitions have got nowhere, this seems like a sensible idea.
I have been previously affected by the Comtrend devices supplied with BT Vision so know firsthand how badly they can affect reception of the HF spectrum within a radius of a few hundred metres.
I think all UK Radio Amateurs that can afford to do so should donate to this fund. I know I will be.
http://www.mikeandsniffy.co.uk/UKQRM/database.html
For the benefit of those who are not radio amateurs of shortwave listeners, I have posted a link to the sound file database of the UKQRM group which was set up to combat these infernal devices.
Take a listen to some of the racket recorded on amateurs radios, and you might better understand the pollution of the airwaves that is making our hobby untenable.
ANY device that emits radio interference SHOULD be removed by the regulator (Ofcom). PLT devices are clearly non-compliant so why do not Ofcom remove them forthwith?
They should be thanking amateurs for doing half their job i.e. detection, for them.
There would be no need for a 'fighting fund' if Ofcom carried out their statutory duty in the first place.
The ARRL in the US basically caught the FCC in what could be called a BPL lie, and had to seek court action.
One of the first and largest BPL rollout in the us (Manassas, VA) is going under:
http://www.arrl.org/news/stories/2009/11/19/11206/?nc=1
More information on the US BPL battle can be found at the ARRL website:
http://www.arrl.org/bpl
I got a set of these with BT Vision. Took ages to get to work – picky about surge protected “blocks”.
Couple of day later my neighbour turned up to ask if I had bought anything new, he showed me the radio noise coming out of these – really bad.
Complained to BT, they came and hard wired the Home Hub to the box and got two free viewing packs for a year as a “goodwill gesture”.
(Disclaimer. I'm an Amateur Radio operator, so I may have a certain inherent bias.)
Gee, now where else have we seen this same farce played out recently? There have been BPL (Broadband over Power Line) trials in the US, encouraged by the FCC, many of which were proven to cause harmful interference to licensed users (primarily Amateur Radio) and violate FCC regs. Enforcement was, to put it politely, lax. It took an organized, well-funded legal and regulatory challenge to beat this back.
The primary argument in favor of BPL is that it's cheaper than running proper kit, i.e., coax or optical fiber, especially in underserved rural areas, and gets the utility companies in on the Internet gravy train. The drawback is that power lines make great radiating antennas and lousy broaband data conduits. Performance has been poorer than advertised, interference problems worse than promised, and the economics haven't turned out well, either.
While it may have useful application in some regions, wide use of BPL is a Bad Idea, and the sooner it is staked in the heart and buried with a head of garlic in it, the better.
This really shouldn't be necessary, but if the regulator won't regulate then hats off to the RSGB for standing up.
The short wave is the only part of the spectrum which can deliver international communications wirelessly, and when you're trying to receive femtowatts or less of signal you certainly don't want all and sundry splattering interference all over it. If you're not specifically using these frequencies for what they alone can do, kindly don't pollute them.
I shall be putting a few quid into the kitty, even though I can't really afford it.. Ofcom: Fail. As ever.
So if you hang around the ham forums, you'll hear a lot of bitching but little action. No one complains to the gov't and if you suggest it, they just say "that's pointless, it won't do any good"
So the hams complain the gov't does nothing, and the gov't does nothing because it hasn't heard any complaints.... Sigh. Clearly a Paris Hilton level of intelligence here.
@Gene Cash
Which ham forums have you hung around? Have you hung around UKQRM at all?
I'm surprised that you are openly willing to admit to having a Paris Hilton level of intelligence, although your post does seem to be a little challenged.
Mods - As an aside, can we have a Joey Deacon icon please?
To say there have been no complaints to the gov't is clearly wrong.
The UKQRM group, and many individuals, have made numerous representations to mp's and various dept's only to get fobbed of with the Ofcom 'message' that there have only been a few claims of interference from amateurs and swl's therefore there is not a real problem.
There have also been 2 petitions to Downing Street, both of which resulted in ministerial waffling, whitewashing responses.
Regardless of who 'hears' interference and who complains about the interference - the fact remains that interference to shortwave bands IS being caused by plt devices and it IS Ofcom's statutory duty to deal with ALL cases of interference.
The issue is that they (Ofcom) are choosing to ignore the issue of plt interference. This inevitably leads to the suspicion that Ofcom is being driven by a hidden agenda. Probably this agenda is to support BIG BUSINESS at the expense of the LITTLE MAN.
This stance of non regulation by Ofcom is what is being challenged.
@Theicom:
There are two distinct flavours of PLT - One is used to connect a home to a network (access) and that which is used to transfer data around the home. Domestic PLT is what is under discussion here.
There is possibly some credance in access PLT - but there is absolutely none for domestic PLT. It just means that people can't be bothered with running Cat-5 cable around their house or setting up a wireless router. Its being marketed as a convenience and has no technical merit.
"No one complains to the gov't and if you suggest it, they just say "that's pointless, it won't do any good"
You don't say which amateur radio forums you waste your time lurking in but if it's uk.amateur.radio anyone posting there is not representative of the hobby and spending anytime there could lead to a warped mind. Luckily we are not all dried up moaning minnies!
M0WYM
Powerline networking is absolutely /filthy/. Most people's home electrical wiring is not conveyed using 13A CAT-5 with balanced line couplers! Every light switch, every junction and solder joint and discontinuity of any kind in the path becomes a signal radiator, and that includes the path out of the house and up the street! Take a look at the graphs, see for yourself:
ref: BBC R&D http://www.bbc.co.uk/rd/pubs/whp/index.shtml
WHP067: The effects of power-line telecommunications on broadcast reception: brief trial in Crieff; J.H. Stott, J. Salter; http://www.bbc.co.uk/rd/pubs/whp/whp067.shtml
WHP099 PLT and broadcasting - can they co-exist?; J.H. Stott; http://www.bbc.co.uk/rd/pubs/whp/whp099.shtml
Natrium hydroxide above would be better served learning about the spectrum. The amateur allocation - far from being bloated is quite small in the microwave regions where antenna sizes are sensible enough to be use for wireless. Yes you could plunder the shortwave allocations - but who wants a wifi antenna 20m long attached to their netbook?
Tried wireless, found flaky connections and slow speeds. My dLan 200Mbps transceivers consistently max out the ethernet ports on my pcs. True plug and play, unlike wireless networking, and with longer range.
The problem I see with Broadband Access over power lines is that the regulations for operating and connecting anything inside a distribution sub-station are strict. 11kV can make a big mess of you. Basically you cannot fiddle with anything that does not have an earth solidly applied to it. This will make setting up the network awkward.
The other idea is that this technology could be used to reach out to remote areas. These are generally fed at 11kV, with pole mounted transformers near the consumer. The transformer is strictly optimised for 50Hz. I doubt that the high frequency broadband will get through without the levels being so high that the transformer is at risk of damage from the extra harmonic losses. If anyone can cite some studies I'd like to see them.
I mean, seriously, what's the point of powerline. If you have to lay a cable to the device, it's usually not a problem to put a second cable there. Otherwise you can use WLAN which is no more or less secure, but at least works much of the time.
Shortwave is unfortunately the only frequency range where broadcast radio is possible. Experiments with higher frequencies have failed, as those waves are no longer reflected by the ionosphere. For example I cannot recieve a single british station via DVB-T, however it's trivial for me to recieve stations via shortwave.
There's a choice - you can either
1) Run a cable from your upstairs study into the loft, buying the trunking, making a hole in the ceiling. Then across the loft to another room where the cable can go down. Hole in the ceiling again.
More trunking, then either use a specialist hole cutter to cut a hole in the huge floor grade chipboard, or dig up the nails with a screwdriver and an industrial strength tack remover or a hammer, cut hole, replace.
Another hole in the ceiling of the room below. Lots more trunking, eventually reaching your endpoint.. When happy, paint over trunking to disguise it.
Time : hours. Expense : not inconsiderable. Effort : lots. Nice, fast and interference free though.
(or a hole to outside, piping, another hole to inside the house. Buying a very large drill, fitting piping or external grade CAT5 to wall, in through the house again with more trunking)
2) Stick in a wireless access point. Find it conflicts with the other 10 wireless access points, drops out and provides shit speeds.
Time : minutes. Expense : low. Effort : minimal, but it may not actually work
3) Spend fifty quid. Put one homeplug device in one socket. One in the other. Run short cable from each one. Job done.
Time : Seconds. Expense : 35-60 quid. Effort : none. Speed and reliability : high
Now replace the above scenario with cabling to another room.. More trunking, more holes, more effort. Homeplug? Unplug, move to other room, plug back in.
I've got a very small amount of sympathy for the fact some homeplug devices interfere with shortwave, but pretending that 'it's usually not a problem' to install cabling is complete and utter lunacy.
See here for starters: http://www.youtube.com/watch?v=pdcY0Eetvsw
then
http://www.youtube.com/watch?v=G7DfdxjRkpU&feature=related
followed by
http://www.youtube.com/watch?v=R6sYD3C0jo8&feature=related
and then take a trip to the ARRL web site at
www.arrl.org/tis/info/HTML/plc/
That should sort you out.
Charlie.
M0WYM
I'd have said three, and they're all disastrous from the point of view of a clean RF spectrum.
One is where you use the cross-country medium and high voltage distribution networks to transmit a bit of data as well as a lot of kiloWatts. Why, when WiMax is so brilliant (or not)?
Another is where you modulate Ethernet frames onto the link between the substation and the home, and call it powerline broadband. This is what Keith Maclean was mouthpiece for at SSE Telecom a few years back, though I suspect the whole game was actually funded by one of the chipset suppliers who thought they might just get themselves a working demonstration network. Unfortunately for SSE and for the chip people, and indeed for the poor prospective customers who had bought the snake oil, SSE's "full commercial rollout" was always just around the corner, till SSE Telecom became just about invisible.
The economics and the practicalities, let alone the EMC issues, ensured this variety of PLT couldn't work commercially back then, and it's got no better from their point of view since then. Bad luck Keith, hope you've got a proper job again now.
And then there's powerline broadband to create short distance networks around the home (or maybe small offices). This is the only one that involves a few boatloads of BT Vision kit though, and that (BT Retail's BT Vision-related hardware and its associated EMC issues) is where one problem really lies.
You can bet your bottom dollar that the DSL people inside BT (Martlesham and everywhere else that needs a low-noise RF environment eg the VDSL people, the day to day DSL faults people, etc) want this kit junked. They may not be allowed to say so in public though. On the other hand the "here's a business opportunity for us to tap" people in BT Retail don't want it junked. Should be interesting to see who wins if BT HQ ever get to hear the true facts. Ofcom obviously only listen to BT Retail (as evidenced by Phorm...).
Way to go RSGB.
Thank you El Reg for publicising this. I will get into my Spectrum Patrol Vehicle and pop over to make my donation. Spectrum is green (hopefully).
Megaphone because trying to make low level RF comms (y'know, like xDSL, not just ham stuff) work while there's PLT nearby is like listening to whispering while someone's feeding maximum level pink noise through a megaphone in your other ear.
I wish Ham's would stop whining about interference on their precious analogue bands isn't about time the RSGB ditched analogue and get with the 21st century! Bang the Rocks Together ! QRX.
Much amateur radio traffic is digital these days. Modes like BPSK31 come to mind. These modes suffer from interference just as much as the analogue modes.
It's not just radio amateurs. What about the people trying to listen to short wave broadcast radio. The numbers of people listening may be small but that does not make it right for electromagnetic compatibility laws to be ignored.
Have I missed someone asking the question: 'why would a street crammed with short range powerline-networked houses encounter less problems than with a street full of WiFi networks?' ?
Slightly off-topic perhaps, but seems like an unmentioned elephant nevertheless...
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